Based on years of experience of building FE's, several of the builders here, including myself, can spec a custom camshaft for you.
I believe Blair uses Bullet and Barry uses Crane/Comp.
I use Comp Cams and Bullet, with Comp grinding the majority of my cams. Each cam is custom ground per the engine's needs and the customer's desires. Individual lobes are chosen, based on the advertised duration, .050" duration, lobe intensities, LSA, ICL, and lift to get where the engine needs to be.
You are wise in looking for a custom camshaft. I really don't see any shelf cams from the major cam manufacturers that work well for an FE, especially in the hydraulic roller flavor.